== Magnetostatics Analysis==
[[EM.Ferma]] solves At very low frequencies, as ω→0 and k<sub>0</sub>→0, one can derive the Poisson equation for the magnetic vector potential subject to specified boundary conditions:
<math>\Delta \mathbf{A} (\mathbf{r}) = \nabla^2 \mathbf{A}(\mathbf{r}) = - \mu \mathbf{J}(\mathbf{r}) </math>